2019-12-24 23:48:36 -0600 commented question How to make Taylor expansion with fixed numerical precision? Thanks @Nasser. What I need is a numerical solution. 2019-12-24 22:37:23 -0600 asked a question How to make Taylor expansion with fixed numerical precision? Following command f(x)=sin(x) taylor(f,x,1.0,2)  shows result: x |--> -0.4207354924039483*(x - 1.0)^2 + 0.5403023058681398*x + 0.30116867893975674  The precision of result has too many bits, what I want is 3 bits, such as: x |--> -0.420*(x - 1.0)^2 + 0.540*x + 0.301  How to do it? Thanks for your help. 2019-09-13 04:31:37 -0600 asked a question More physics constants in Sagemath I can you following command to load physics constants h and c:  from scipy.constants import h, c h, c # show value of h and c  But, how can I load more physics constants such as Bohr magneton? Following command doesn't work,  from scipy.constants import Bohr magneton Bohr magneton # to show Bohr magneton  I load physics constant from https://docs.scipy.org/doc/scipy/refe... Thanks for help. 2019-09-08 01:53:38 -0600 commented question How to show more results in sagemathcell? Thanks slelievre, is it possible to display full output in sagemathcell (not in Jupyter), not only last result? @slelievre 2019-07-04 04:22:14 -0600 received badge ● Nice Question (source) 2019-07-03 08:56:25 -0600 asked a question Is there a way to remove "Terms of Service" popup? My dear friends, after using sagemath for a few of month, I want to introduce more people to use sagemath, because sagemath is really useful and powerful. I live in China, and we have GFW, hence mnay site such as google, facebook, are blocked. I am not sure if sagemath.org would be blocked, hence I want to setup own sagemath server. Thanks for the open source of sagemath, I almost have my own sagemath server! When I try embedded sagemath code in some sagemathcell, and Evaluate code, it always popup the "Terms of Service". Is there a way to remove it? Please visit http://sagemath.askplanck.cn Put any sagemath code, such as, 1+2 You will find the popup. Thanks for help! John 2019-05-29 22:33:14 -0600 commented answer How to show more results in sagemathcell? Thank you very much. I am working of @slelievre 's suggestion. 2019-05-26 20:27:09 -0600 commented answer How to show more results in sagemathcell? Thank you, FrédéricC and Juanjo. But your answers is not what I want. I wish the ouput has 3 lines. My example is for simplity, other example cannot be written as an array. Is there any other suggestion? 2019-05-26 07:47:46 -0600 asked a question How to show more results in sagemathcell? If I put following comand in http://sagemath.askplanck.cn/ 1+2 10+20 100+200  If Evaluate above command, I can only get last result: 300. What I wish is too get 3 results one by one in my own sagemath server , How can I do in configure file. In https://cocalc.com/, if I put above comand, it shows 3 results. This is nice,and is what I want. Is it possible in such like sagmathcell? PS. I don't want to put command as following (which can show 3 results): print 1+2 print 10+20 print 100+200  Thank you very much for your suggestion. John 2019-04-11 01:37:26 -0600 commented answer Cannot solve differential equation (Lane-Emden equation) numerically Thank you very muchfor you nice answer, Mr. Buring. For the first plot, is there a simple way to find t where y0=0? 2019-03-07 19:48:45 -0600 received badge ● Supporter (source) 2019-03-07 19:48:42 -0600 received badge ● Scholar (source) 2019-03-07 07:48:56 -0600 received badge ● Student (source) 2019-03-07 07:29:18 -0600 received badge ● Editor (source) 2019-03-07 05:06:38 -0600 asked a question Cannot solve differential equation (Lane-Emden equation) numerically Hi, my friends, I tried to solve Lane-Emden equation, as model of white dwarf, $$\frac{d^2x}{dt^2} +\frac2 t \frac{dx}{dt} + x^n = 0, ~~~~ where ~~~~n=\frac 3 2$$ and I have some troubles in sagemath. I am using following code: T = ode_solver() def f_1(t,y): return [y[1],-2/t*y[1]-y[0]^(3/2)] T.function = f_1 def j_1(t,y): return [[0, 1], [-3/2*y[1]^(1/2), -2/t], [0,2*y[1]/t^2]] #Jacobian matrix T.jacobian = j_1 T.algorithm = "rk8pd" T.ode_solve(y_0=[1,0], t_span=[0,10], num_points=1000) f = T.interpolate_solution() plot(f, 0, 10)  Above code is very similar of the example in sagemath reference: Van der Pol equation Both equations (Lane-Emden and Van der Pol) are non-linear differential equation, therefore, are not easy to solve. I don't know where comes to problem in above codes, can someone give me a help? John